John wants to retire in 15 years. He wants to have an income of $50,000 per year for 20 years after he retires. He can invest in an annuity that pays 5% interest compounded annually. How much should he invest in the annuity each year to reach his goal?
a. $3,004.17
b. $4,569.32
c. $5,783.43
d. $6,125.09